The objective of the proposed studies is to investigate quantitative [F- 18]fluorodeoxyglucose (FDG) Positron Emission Tomography (PET) as a measure of non-small cell lung cancer (NSCLC) aggressiveness in vivo (i.e. grading) and to make comparisons with patients' outcomes and with specimen-derived measures of cellular proliferation previously shown to predict poor outcome (S-phase fraction, Ki-67 index). We postulate that, in clinically resectable NSCLC patients, pre-operative FDG PET will show that tumors with higher FDG uptake: (a) will recur sooner after surgical resection than same stage tumors with low uptake; (b) are more likely to have mediastinal or distal metastatic disease than tumors of the same clinical stage but low uptake; (c) have higher S-phase fraction of Ki-67 scores in their resected specimen. The specific aims of the proposal are: (1) Perform whole-body pre- operative FDG PET imaging and correlate FDG uptake in primary NSCLC with outcome. FDG uptake will be quantified by the following methods that will be compared. Standardized Uptake Value (SUV) and SKM-FDGMR (FDG Metabolic Rate determined by a Simplified Kinetic Method). (2) Perform whole-body pre-operative FDG PET imaging and correlate FDG uptake (quantified as SUV and SKM-FDGMR) in primary NSCLC with disease extent as demonstrated by PET and surgical staging. (3) Correlate pre-operative FDG uptake in primary NSCLC with markers of cellular proliferation measured from the resected specimen and previously shown to predict poor outcome. Outcome will be measured by recurrence-free survival, time-to recurrence and survival. In summary, by studying NSCLC patients pre-operatively, prior to any form of chemotherapy or radiotherapy, we will gain valuable information about the biology of lung cancer, the leading cause of cancer death in the United States. By performing a biologic grading of resectable NSCLC with FDG PET, we will predict which patients will have a worse outcome. This information will allow individualized therapy.